How C# Generics make your apps MUCH faster

Here is how C# generics make your apps much faster

[surgeon]

good old arraylists, it's like christmas, you never know what you gonna get

[ZintomV]

For more context, the JIT will compile a new class/method with the type hard coded in, so a List<int> is literally just a List with a special name but the "_items" array is compiled as a int[] rather than object[], in other words, everywhere "T" is used gets replaced by the type provided at runtime.

[jongeduard]

Suprising thing is that to this day PowerShell still highly depends on non-generic dotnet types and a ton of boxing. It's completely working with object arrays, ArrayLists and HashTables. All things considered very legacy in C#.
As a scripting language it automates a LOT of stuff, that's the nice side of it. The JavaScript-style loosely typedness makes it very easy to write.
But yeah, when it comes to performance? Nope. Goodness!

[kylekeenan]

It was nice to hear about the history of c# thanks.

[Deltacasper]

Nice. Probably the best improvement to c# along side hot reload.

[whaisonw]

Yes, a List does not need to store references to the objects on the heap but the entire List must be allocated in the heap because it is growable. Nonetheless the items can be stored "next" to each other

[userc]

Can you please compare between generics in C# and Java in terms of performance and internals

[cerulityk]

Generics and interfaces. If you want a Var generic class, you can make an interface called IVar that is not generic that Var implements to use Vars of any type in your program.

[jacopobingewatching]

if IRC the boxing and perpetual casting is Java's way of doing generic lists, whereas .NET recompiles the generic into it's own "specific" type implementation.
Not to shit on java... but.

[Blaisem]

does the performance boost of generic collections only apply to primitives and structs, or also to your custom types?

[johnathankrausrig]

You tried to get primitives together to justify a objects back in the days. Generics are really awesome, the only thing i miss is to use generic methods with annonymous types.always reflecting or work around it is the only drawback

[justchillout]

Sometimes better to use HashSets instead of Lists especially when huge amount of data is loaded

[rushas]

Great video! I'd love to watch a more in depth video about generics

[slashd]

But why did they call it Generic List and not Specialized List which would be a more descriptive name? 🤔
Everyone knows what specialized means, thats not the case with generic

[qmster]

How long ago was this?
I remember it being a normal language back in MVC3

[HistoireDuViolet]

But reference types can be allocated on stack.

[david]

Does that mean that C#2 didn't make use of the stack? :O

[magicspider]

I have to comment on the 69 and 420 he always uses as test data, please keep it up and don't address it.

[nothingtoospecial]

Too bad that they introduce run-time overhead! Compile-time generics would be a lot better!

[vothaison]

Thanks Microsoft for not ruin the best language.